1. Field of the Invention
The present invention relates to a propulsive apparatus for propelling an electric vehicle with at least a propulsive motor used as a propulsive source which is coupled to a drive shaft by a constant velocity joint.
2. Description of the Related Art
Some automobiles which include four-wheeled and two-wheeled vehicles have a propulsive motor as a propulsive source. Such automobiles are exemplified by hybrid vehicles which incorporate both an internal combustion engine and a propulsive motor as propulsive sources and electric vehicles or fuel-cell electric automobiles which incorporate a propulsive motor as a propulsive source.
On the electric vehicles, the rotational propulsive power generated by the propulsive motor is transmitted through a drive shaft to drive wheels, i.e., tires. As a result, the drive wheels are rotated to propel the electric vehicles.
The propulsive motor and the drive shaft are connected to each other by a constant velocity joint. Occasionally, the propulsive motor, the drive shaft, and the constant velocity joint are jointly referred to as “propulsive apparatus” or “power unit”. The present applicant has proposed a power unit including a propulsive motor, a speed reducer mechanism, and a constant velocity joint which are housed in a case, as disclosed in Japanese Patent No. 4379867.